I don't believe so. My dad said that the officer who gave it to him had kept it since leaving the military sometime after the Korean War. Has the original holster, too. It's a low serial for Ithaca (within the first hundred pistols) and while it MAY have been rebuilt after WWII, I'm not convinced. Small parts (hammer, mainspring housing, trigger, slide-stop) appear to be Colt style ones with the knurling on, but since it's such a low number, Ithaca might've used existing Colt parts? I couldn't say. Slide is a Korean War-era replacement "hard slide" by Colt. I can't find any indication of arsenal rebuild marks.
Two Ithacas listed on Simpson Ltd's website (one sold, one for sale) both have a number there. One has an 8, the other appears to be a 9; the 8 has a higher serial number than mine, and the possible-9 has an even high serial. A number of Colt pistols have a number in the same place, usually a double-digit. I'm leaning towards it being a Colt quality-control inspection number for finished pistols.